【摘要】 采用真空气相燃烧合成技术制备了超细氧化铋粉体.该技术是在较低的真空条件下,通过加热金属形成蒸气后与氧气发生氧化燃烧反应合成金属氧化物粉体.研究认为,要实现氧化物高纯、超细、粒度和晶形的可控,需通过合理设计反应装置以及对反应过程中各工艺条件的有效控制.着重分析了制备过程对氧化铋粉体的纯度、粒度和形貌的影响.结果表明:反应过程中加热温度、真空度、蒸发速率、通氧流量和反应时间是影响粉体纯度、粒度和形貌的主要因素.采用该项技术所制备氧化铋粉体的晶形和粒度可控,可以制备平均粒径0.5~2.0μm、纯度大于99.9%的微米和亚微米级超细氧化铋粉体,是一项低成本、无污染、流程短、易实现规模化的清洁化工艺技术.更多还原

【Abstract】 Superfine powder of bismuth oxide was prepared by vacuum gas combustion.The vacuum gas combustion technique is based on an oxidation reaction between metal vapour formed by application of heat in a lower vacuum and oxygen.Researches show that in order to obtain metallic oxides with high purity,superfine,granularity and controllable polytype,the reaction equipment is needed to be rationally designed and the process conditions are needed to be controlled effectively.The effects of preparation process on the purity,particle size,morphology of bismuth oxide powder were analyzed in the paper.The results show that the heating temperature,degree of vacuum,rate of evaporation,and reflux of oxygen are key factors that affect the purity,granularity,and morphology of the powder.The bismuth oxide powder with purity higher than 99%,and mean size between 0.5 μm and 2.0 μm could be prepared by this technique.It is a clean technology with low cost,no pollution and short flow chart,and is easy to scale up.更多还原